Regional bank stocks hit all-time highs on Wednesday, but analyst Jack Micenko told CNBC on Wednesday he has concerns about the sector.

"One, loan growth has been very anemic. Loan growth has actually decelerated since the election. And second, as the Fed continues to raise rates, the impact from rising deposit costs has risen exponentially as well," the associate director of research at Susquehanna Financial Group said in an interview with "Power Lunch."

However, Micenko said he believes regional bank stocks fully reflect the anticipated tax and regulatory reform.

"The core drivers of earnings growth are not there. We took our estimates down on 90 percent of our coverage coming out of the third quarter. We need to see some loan growth … to get more constructive," he said.

"While the group has had a run, if you look at relative multiples, today versus where we are prior to the election, they really haven't gone up too much despite the fact that this group is levered to higher rates, lower corporate tax rates as well as this regulatory rollback theme," he told "Power Lunch."